It has been asked before:
Including one where you were involved and I replied:
Basically the toggleEditors command should work just fine but it seems there is some kind of "intercept" from TinyMCE which stops the accelerator that you bind to that command from working back the other way - related issue: Desktop: Command "moveToFolder" when bound to an accelerator only works when focus is on codemirror editor · Issue #6063 · laurent22/joplin · GitHub